Speed controlling device



March 11, 1941. T LAN 2,234,181

SPEED CONTROLLING DEVIGB Filed June 19, 1940 uunusm INVENTOR Wn'LtE'r' TLung Manx ATTORNEY Patented Mar. 11, 1941 PATENT OFFICE SPEEDCONTROLLING DEVICE,

Walter T. Lang, Metuchen, N. J.

Application June 19,

3 Claims.

1940, Serial No. 341,303

(Granted under the act of March 3, 1883, as

amended April 30,

This invention relates to a device for limiting the maximum clockwise orcounterclockwise rtation of a shaft adapted to be rotated at variablespeeds to the same speed or predetermined proportional part of thespeed. at which another shaft is driven.

It is an object of the invention to provide a simple and accurate deviceadapted for use in computing mechanisms for limiting the rotation of ashaft designed to be rotated in proportion to a given quantity to aspecific limit which is governed by the rate of rotation of anothershaft.

A further object of the invention is to providea speed controllingdevice particularly adapted for limiting the angular or linear rate of ashaft in a fire control director to a speed of rotation not to exceed agiven limit, as for example, the constant speed at which the disk isdriven in a disk-and-roller type of rate mechanism or some predeterminedproportional part of the disk speed.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferred25 embodiment as shown in the accompanying'drawing in which:

Fig. l is a plan view of the device;

Fig. 2 is an elevational view partially in section showing theinvention.

Referring now to the drawing by characters of reference there is shown aconstant speed motor H! of any desirable conventional design disposed indriving relation with a shaft I I having a worm l2 affixed thereto.

A second shaft I4 suitably journaled for rotation in any well knownmanner is disposed to be driven by shaft worm l2 and a worm wheel i3afiixed to shaft M. The worm t2 and worm Wheel l3 are of thenon-reversible type so that shaft I4 may be driven in one directiononly.

A pair of overrunning clutches l5 and I6 are moimted in any suitablemanner in concentric relation to shaft l4 and each comprises an innerelement rigidly secured to shaft M for rotation therewith. The otherelement I8 of each of the clutches is suitably mounted for relativerotation concentrically of the shaft I4 in either a clockwise orcounterclockwise direction and is formed as indicated at H) with aclutch surface adapted to engage a cooperating clutch surface on a pawl20 carried by the corresponding inner clutch element I! when the speedof rotation thereof tends to become greater than the speed or apredetermined fractional part of the speed of rotation of the shaft I4and corresponding inner clutch element. I

In the embodiment shown a shaft 2| which is rotatable in proportion toany desired quantity and whose speed of rotation is to be limited toeither the speed, or some predetermined proportional part of the speedof rotation of shaft I4, is suitably mounted in any conventional type ofbearings and provided with a gear 22 afiixed thereon disposed in drivingrelation with the outer clutch elements l8. Rotation of shaft 2| willeffect rotation of the outer clutch element 8 of clutch l5 and theclutch surface 9 and pawl 26 of this clutch are so arranged as tointerlock when shaft 2| is rotated in a counterclockwise direction, asviewed in Fig. 2 from the left end of the shaft, at a speed of rotationsuch that the outer clutch element of clutch I5 tends to be driven at agreater speed of rotation than shaft Hi. The corresponding parts ofclutch 6, that is, the clutch element l8 and the pawl 20 of this clutchare designed to remain disengaged or overrun upon counterclockwiserotation of shaft 2|. Upon clockwise rotation of shaft 2| one wayclutches l5 and I6 wil1 function in a manner just the reverse of thatdescribed for counterclockwise rotation of shaft 2|.

While in the embodiment herein disclosed the clutches l5 and I6 havebeen shown as of a specific character it will be understood that anydesirable type of overrunning clutch may be employed and that the innerelements of the clutches may be arranged to be driven by shaft 2| andthe outer elements by shaft I4, moreover, if desired the inner elementsof the clutches may be arranged to be driven in relative reversedirections by shaft I4 throughany conventional gear system for thepurpose, and the outer elements arranged to be driven in the samerelative direction by the shaft 2| through a similar gear system.

The clutches may be selected to be of the type that will lock movementof shaft 2| when shaft I4 is stationary and lay-substituting a geartrain of suitable ratio for the gear 22 the limit of speed of rotationof shaft 2| in either clockwise or counterclockwise direction may belimited to a proportional part of the speed of rotation of shaft l4, orto different limits in clockwise and counterclockwise rotation, or toupper and lower limits in either clockwise or counterclockwise rotation.

In the normal operation of the device the constant speed motor ID willdrive shaft M at a. constant speed through the non-reversible wormgearing l2 and I3 and shaft 2| will be manually or otherwise suitablyrotated which will effect the inner clutch element '20 will engage thesurface IS on outer clutch element l8 of clutch I5 and limit the speedofshaft 2| by reason of the fact that shaft 2l cannot accelerate or change7 the speed of shaft l4 due to the non-reversible gearing l2l3. Duringclockwise movement of shaft 2| at normal speed clutch l6 merelyoverrides, but upon clockwise movement of shaft 2| beyond normal speed,clutch l6 will function, {in

the same manner as clutch l5 functions in counterclockwisemovement ofshaft 2|, to limit the clockwise speed of rotation of shaft 2 l.

Theflmotor ID, in' the, arrangement disclosed maybe one of low'powersince the clutches are arranged to act'on shaft I 4 through thenonreversible gearing l2- l 3 reversely, and where the device is to :beinstalled in, for example an existing fire control director the constantspeed motor'originally installed in the director will suffice for. usewith the device.. Having now described a present'preferredembodi'mentofthe invention I claim:

1;. In a speed limiting device in combination,

'a shaft, means, for non-reversibly rotating the shaft at a'cons tantspeed, a pair of overriding clutches, means operablyco'nnectingcorresponding. elements of saidclutches to the shaft formovement thereby, a second shaft and, means connecting the second shaftto corresponding elements of said clutches cooperating with said firstrecited elements whereby rotation of said second shaft relative torotation of said first shaft will be limited to a predetermined speedproportional to the speed of said first shaft.

2. In a speedlimiting device in combination, a shaft, means fornon-reversibly rotating the shaft at a constant speed, a pair ofoverriding clutches having cooperating clutch elements, means o perablyconnecting corresponding cooperating elements of said clutches to theshaft for rotation in the same direction thereby, a second shaft, andmeans connecting the second shaft to corresponding elements of saidclutches cooperating with said first recited elements for relativereverse rotation upon rotation of said second shaft whereby relativereverse rotation of said second shaft will be limited to a predeterminedspeed proportional to the speed of said first shaft.- 1

v3. "In a speed limiting device in combination,

a shaft, means for'non-reversibly rotating the shaft at a constantspeed, a pair of one way overriding clutches having inner and outerelements, means mounting the inner elements-on said shaft, meansmounting the outer elements of said clutches for movement relative tosaid inner elements, said outer elements being engageable with theircooperating inner elements in relative reversedirections of movement, asecond shaft, and means connecting the second shaft to said outerelements for relatively reversely rotating said outer elements wherebyrelative reverse rotation of said second shaft will be limited to apredetermined speed proportional to the speed of said first shaft.

' v WALTER T. LANG.

